The library uses an opaque data type to represent a tree structure
made of strings, data blocks, arrays and dictionaries (key-value pair
lists). This structure can be manipulated, written out to and read in
from a file, and synchronized with the contents of a file.
The purpose of PL is to closely mimick the behaviour of the property
lists used in GNUstep/OPENSTEP (there formed with the NSString,
NSData, NSArray and NSDictionary classes) and to be compatible with
it. PL enables programs that use configuration or preference files to
make these compatible with GNUstep/OPENSTEP's user defaults handling
mechanism, without needing to use Objective-C or GNUstep/OPENSTEP
themselves.
